Patch "Input: xpad - prevent spurious input from wired Xbox 360 controllers" has been added to the 4.5-stable tree

This is a note to let you know that I've just added the patch titled

Input: xpad - prevent spurious input from wired Xbox 360 controllers

to the 4.5-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
input-xpad-prevent-spurious-input-from-wired-xbox-360-controllers.patch
and it can be found in the queue-4.5 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Cameron Gutman <[email protected]>
Date: Fri, 27 May 2016 16:23:50 -0700
Subject: Input: xpad - prevent spurious input from wired Xbox 360 controllers

From: Cameron Gutman <[email protected]>

commit 1ff5fa3c6732f08e01ae12f12286d4728c9e4d86 upstream.

After initially connecting a wired Xbox 360 controller or sending it a command to change LEDs, a status/response packet is interpreted as controller input. This causes the state of buttons represented in byte 2 of the controller data packet to be incorrect until the next valid input packet. Wireless Xbox 360 controllers are not affected.

Writing a new value to the LED device while holding the Start button and running jstest is sufficient to reproduce this bug. An event will come through with the Start button released.

Xboxdrv also won't attempt to read controller input from a packet where byte 0 is non-zero. It also checks that byte 1 is 0x14, but that value differs between wired and wireless controllers and this code is shared by both. I think just checking byte 0 is enough to eliminate unwanted packets.

The following are some examples of 3-byte status packets I saw:
01 03 02
02 03 00
03 03 03
08 03 00

---
 drivers/input/joystick/xpad.c |    4 ++++
 1 file changed, 4 insertions(+)

@@ -455,6 +455,10 @@ static void xpad_process_packet(struct u
 static void xpad360_process_packet(struct usb_xpad *xpad, struct input_dev *dev,
 				   u16 cmd, unsigned char *data)
 {
+	/* valid pad data */
+	if (data[0] != 0x00)
+		return;
+
 	/* digital pad */
 	if (xpad->mapping & MAP_DPAD_TO_BUTTONS) {
 		/* dpad as buttons (left, right, up, down) */

Patches currently in stable-queue which might be from [email protected] are

queue-4.5/input-xpad-prevent-spurious-input-from-wired-xbox-360-controllers.patch